When work must be done in an existing location that is occupied, as for example a plaster wall has to be cut, considerable dust and air-blown particles will travel throughout the space being worked upon and into areas not being worked upon. It is therefore necessary in some way to seal off the area being worked upon so that the air-blown particles will not travel beyond that area. In the past, attempts have been made to use drapes, but it is always a problem as to how to fasten the drapes. Nailing to existing structures tends to damage the structure and there exists, therefore, a need to have a simple yet portable structure which can be easily erected by one person and which will seal off the area being worked upon.
In the prior art, there is disclosed a number of curtain wall structures that are primarily designed for a mine ventilation control which have some analogy to the present invention; for example, in the North Patent, U.S. Pat. No. 1,398,909, there is disclosed a curtain wall which is supported by legs, the upper end of each of the legs having a plate on which the curtain may hang. In the Shacikoski Patent, U.S. Pat. No. 2,621,725, another curtain wall is shown being supported by legs and there is illustrated an element 10 which is supported to the ceiling of the mine shaft by brackets as well as being supported at the end by the legs. A disclosure of a spring-loaded leg is seen in the Burgess Patent, U.S Pat. No. 3,118,363, while the Connelly Patent, U.S. Pat. No. 443,133, illustrates a drapery holder consisting of a pair of legs with a bar as a cross member.